/*
 * Copyright 2002-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.beans.support;

import java.io.Serializable;

import org.springframework.util.StringUtils;

/**
 * Mutable implementation of the {@link SortDefinition} interface.
 * Supports toggling the ascending value on setting the same property again.
 *
 * @author Juergen Hoeller
 * @author Jean-Pierre Pawlak
 * @see #setToggleAscendingOnProperty
 * @since 26.05.2003
 */
@SuppressWarnings("serial")
public class MutableSortDefinition implements SortDefinition, Serializable {

    private String property = "";

    private boolean ignoreCase = true;

    private boolean ascending = true;

    private boolean toggleAscendingOnProperty = false;


    /**
     * Create an empty MutableSortDefinition,
     * to be populated via its bean properties.
     *
     * @see #setProperty
     * @see #setIgnoreCase
     * @see #setAscending
     */
    public MutableSortDefinition() {
    }

    /**
     * Copy constructor: create a new MutableSortDefinition
     * that mirrors the given sort definition.
     *
     * @param source the original sort definition
     */
    public MutableSortDefinition(SortDefinition source) {
        this.property = source.getProperty();
        this.ignoreCase = source.isIgnoreCase();
        this.ascending = source.isAscending();
    }

    /**
     * Create a MutableSortDefinition for the given settings.
     *
     * @param property   the property to compare
     * @param ignoreCase whether upper and lower case in String values should be ignored
     * @param ascending  whether to sort ascending (true) or descending (false)
     */
    public MutableSortDefinition(String property, boolean ignoreCase, boolean ascending) {
        this.property = property;
        this.ignoreCase = ignoreCase;
        this.ascending = ascending;
    }

    /**
     * Create a new MutableSortDefinition.
     *
     * @param toggleAscendingOnSameProperty whether to toggle the ascending flag
     *                                      if the same property gets set again (that is, {@code setProperty} gets
     *                                      called with already set property name again).
     */
    public MutableSortDefinition(boolean toggleAscendingOnSameProperty) {
        this.toggleAscendingOnProperty = toggleAscendingOnSameProperty;
    }


    /**
     * Set the property to compare.
     * <p>If the property was the same as the current, the sort is reversed if
     * "toggleAscendingOnProperty" is activated, else simply ignored.
     *
     * @see #setToggleAscendingOnProperty
     */
    public void setProperty(String property) {
        if (!StringUtils.hasLength(property)) {
            this.property = "";
        } else {
            // Implicit toggling of ascending?
            if (isToggleAscendingOnProperty()) {
                this.ascending = (!property.equals(this.property) || !this.ascending);
            }
            this.property = property;
        }
    }

    @Override
    public String getProperty() {
        return this.property;
    }

    /**
     * Set whether upper and lower case in String values should be ignored.
     */
    public void setIgnoreCase(boolean ignoreCase) {
        this.ignoreCase = ignoreCase;
    }

    @Override
    public boolean isIgnoreCase() {
        return this.ignoreCase;
    }

    /**
     * Set whether to sort ascending (true) or descending (false).
     */
    public void setAscending(boolean ascending) {
        this.ascending = ascending;
    }

    @Override
    public boolean isAscending() {
        return this.ascending;
    }

    /**
     * Set whether to toggle the ascending flag if the same property gets set again
     * (that is, {@link #setProperty} gets called with already set property name again).
     * <p>This is particularly useful for parameter binding through a web request,
     * where clicking on the field header again might be supposed to trigger a
     * resort for the same field but opposite order.
     */
    public void setToggleAscendingOnProperty(boolean toggleAscendingOnProperty) {
        this.toggleAscendingOnProperty = toggleAscendingOnProperty;
    }

    /**
     * Return whether to toggle the ascending flag if the same property gets set again
     * (that is, {@code setProperty} gets called with already set property name again).
     */
    public boolean isToggleAscendingOnProperty() {
        return this.toggleAscendingOnProperty;
    }


    @Override
    public boolean equals(Object other) {
        if (this == other) {
            return true;
        }
        if (!(other instanceof SortDefinition)) {
            return false;
        }
        SortDefinition otherSd = (SortDefinition) other;
        return (getProperty().equals(otherSd.getProperty()) &&
                isAscending() == otherSd.isAscending() &&
                isIgnoreCase() == otherSd.isIgnoreCase());
    }

    @Override
    public int hashCode() {
        int hashCode = getProperty().hashCode();
        hashCode = 29 * hashCode + (isIgnoreCase() ? 1 : 0);
        hashCode = 29 * hashCode + (isAscending() ? 1 : 0);
        return hashCode;
    }

}
